新型Guerbet两性离子表面活性剂的溶液性质

Characteristics of a Novel Guerbet Zwitterionic Surfactant Aqueous Solution

对合成的新型Guerbet两性离子表面活性剂N-(3-支链十六烷基聚氧乙烯醚(3)-2-羟丙基)-N,N-二甲基羧酸甜菜碱(C16GPE3B)的表面张力(γ)进行了测定,确定了其临界胶束浓度(CMC)及γCMC,并通过计算获得了其在界面上的饱和吸附量、最小分子吸附面积和标准胶束化自由能。用旋滴法测定了C16GPE3B的无机盐(NaCl)或弱碱(Na2CO3)溶液与原油间的油水动态界面张力;采用Washburn方法测定了C16GPE3B水溶液在硅胶固体表面的相对接触角以及对硅胶表面模拟油的脱油效率,并将C16GPE3B的脱油效率与十六烷基三甲基溴化铵(CTAB)进行了比较。实验结果表明,在Na2CO3存在下,C16GPE3B溶液与原油能形成超低的平衡油水动态界面张力(1×10-3 mN/m);在脱油效率相当的情况下,C16GPE3B的浓度仅为CTAB的1/50,证明C16GPE3B具有非常优异的驱油能力。

The critical micelle concentration（CMC）,surface tension（γ） and γCMC（γ at CMC） of a novel Guerbet zwitterionic surfactant,N-[3-branched hexadecyloxy-polyoxyethylene（3） ether2-hydroxy-propyl]-N,N-dimethylglycine betain（C16GPE3B）,were determined.Its saturated adsorbance,minimum molecular cross-sectional area and standard free energy of micellization were obtained by thermodynamic calculation.The dynamic oil-water interfacial tension between NaCl-C16GPE3B（or Na2CO3-C16GPE3B） solution and Shengli crude oil was measured by spinning drop method.The contact angle between the C16GPE3B aqueous solution and silica gel,and mimic oil recovery on the silica gel surface were investigated by Washburn method.And the mimic oil recovery with C16GPE3B was compared with that with cetyl trimethyl ammonium bromide（CTAB）.It was indicated that ultralow equilibrium oil-water interfacial tension could form between the Na2CO3-C16GPE3B solution and the Shengli crude oil.The required C16GPE3B concentration was only fiftieth of the CTAB concentration with the same oil recovery.